Re: Natural keys vs Aritficial Keys

"paul c" <toledobythesea_at_oohay.ac> wrote in message
news:CAgQl.28536$PH1.3994_at_edtnps82...
> --CELKO-- wrote:
>>>> Speaking of efficiency, composite primary keys have almost no effect,
>>>> if you get the indexes right. <<
>>
>> Ever work with DBs that use hashing instead of tree indexes? Longer
>> keys are better because there is less chance of a hash collision.
>> There is also a lot of work being done on minimal perfect hashing
>> right now. This is going to be very important for VLDB because
>> unlike indexes, a hash requires only one probe.
>
> Every so often some crackpot claims to have discovered the perfect hash
> but bigger keys usually need bigger buckets to reduce collisions. It
> reminds me of the old joke about the guy who kept re-running his
> compression program in hopes of reducing the file's size to one byte.